Another factor is the reluctance of parents to do what is necessary for their children.

“I have so many parents that come to see me and they say ‘whenever I try to brush my kid’s teeth they just cry, so I just don’t,'” said Dr. Greenspoon.

The lack of fluoride in Montreal’s drinking water puts people on the island at a distinct disadvantage.

Quebec’s Order of Dentists has been pushing for the “simple solution” for many years, urging Montreal to follow the lead of the Dorval and Pointe Claire water treatment plants which supply much of the West Island — an area that, unsurprisingly, has fewer people getting cavities.

Dr. Joelle Lasry said it’s not a surprise.

“It is in the water so parents don’t have to take an active role and give fluoride supplements and so on. In that sense it’s built into the tooth,” said Dr. Lasry.

The city of Montreal said it has no interest in adding fluoride when only one percent of treated water is used for drinking.

To compensate, Dr. Lasry urges parents to monitor tooth brushing until they have teenagers.

“I want parents to be involved in the kids’ brushing until they’re 10 or 11. I encourage them to really be active,” she said.

Dentists are also encouraging parents to bring in their children while their teeth are forming.

“If we can start at one year old and give the parents pointers, the primary teeth will not be affected,” said Dr. Lasry.